Returns or sets the format code for the specified object as a string in the language of the user. Read/write Variant.
The Format function uses different format code strings than do the NumberFormat and NumberFormatLocal properties.
This example displays the number format for the data labels in the first series on the chart, in the language of the user.
MsgBox "The number format for the first series is " & _
myChart.SeriesCollection(1).DataLabels.NumberFormatLocal